I'd like to get something that should satisfy for several years to come, of course I may yet not bother and leave the 601's where they are and live with it, can't say I'm unhappy with them (but you can always want more?), but to me it makes more sense to move those and invest in better fronts that to spend, say £150 on rears that don't get used for music - don't want to seem like I've money to burn, it's something I've been considering for a while.